The figure is almost impossible to imagine: 9,000 tons of sargassum arrive every day and every night on the Caribbean coast of Quintana Roo.
Saying 9,000 tons hardly conveys the scale. Fresh sargassum has an estimated density of 275 kilograms per cubic meter, explains David Jáuregui, technical advisor at Grupo Dakatso and a specialist in marine engineering. With an average thickness of 15 centimeters, that volume is equivalent to 218,182 square meters of sea covered by the brown mass of algae that, once decomposed, gives off a foul odor.
“It smells like rotten eggs, like stagnant water,” said a couple of tourists from Mérida.
It is also equivalent to 30.5 soccer fields, or a strip of coastline 11 kilometers long and 20 meters wide.
The Origin of the Sargassum
The first recorded arrival of sargassum, then referred to as the “golden tide,” occurred in 2011. At first, it was believed to originate from the Sargasso Sea in the North Atlantic.
Researchers later determined that it comes from the Great Atlantic Sargassum Belt, a massive accumulation of marine macroalgae whose growth has been linked to warmer ocean temperatures associated with global climate change.
According to Mexico’s Ministry of Environment (Semarnat), there are currently 90,000 tons (90 million kilograms) of sargassum floating in the Caribbean Sea off the coast of Quintana Roo.
Since 2011, its arrival has become a constant occurrence, although its magnitude continues to surprise residents.
“There are days when you can’t even see the sea because of the sargassum,” said a resident of Playa Coral.
A Changed Coastline
Playa Coral is pet-friendly but nearly deserted. On a typical Saturday morning, not a single visitor is present.
There are almost no waves. The shoreline has become a 10-meter-wide strip of yellow and brown decomposing sargassum.
In many places, there is barely any beach left. The continuous removal of sargassum has accelerated coastal erosion, allowing the sea to reach the roots of the palm trees. Cleaning operations have long since ceased in some areas.
“Tourists arrive expecting to swim in turquoise-blue water, but the sad reality is that there is hardly any turquoise left,” a local resident said while cleaning her sandals against a railing.
Government Response
On Sunday, President Claudia Sheinbaum postponed a conference in Cancún regarding the government’s sargassum strategy in order to attend the FIFA World Cup final in New York.
She explained:
“It is a sign that there is good coordination with the Government of the United States.”
The daily arrival of 9,000 tons of sargassum continues to be regarded as a major environmental emergency.
The People Fighting the Sargassum
The presence of sargassum has become so common that Grupo Dakatso, recognized by the United Nations for developing Sargacrete, an environmentally friendly concrete made with sargassum, has celebrated Sargassum Workers’ Day every June 13 for the past four years.
More than 2,500 people in Quintana Roo work every day collecting the algae, although local residents say the workforce is still insufficient.
At Playa Delfines, the public beach in Cancún’s Hotel Zone, the shoreline beneath the iconic Cancún sign is kept clean. Offshore, however, the turquoise water is interrupted by large dark patches of floating sargassum.
Swimmers often encounter dried algae that can irritate the skin.
Next to the luxury hotels, wide stretches of dried brown sargassum cover the sand. A former fisherman now spends his days operating a tractor to remove it.
“Right now we work from 7:00 to 11:00 in the morning. When there’s too much sargassum, we work from 7:00 until 3:00 in the afternoon. Today they only asked us to work on Sunday because the hotel is expecting visitors,” he explained.
Even after the beach is cleaned, the sand remains scarred, mixed with streaks of brown algae.
Farther down the beach, a couple poses for wedding photographs.
“Sometimes we leave the beach looking like it does today, and when we come back tomorrow it’s completely covered again,” the tractor operator said.
Capturing Sargassum at Sea
The current government strategy focuses on acquiring specialized sargassum collection vessels.
According to David Jáuregui, the world’s largest sargassum collection ship, currently being built by Grupo Dakatso for the Mexican Navy, will be capable of collecting 600 tons per day.
He estimates that at least 15 vessels of that capacity would be needed to collect the entire daily influx.
Jáuregui also emphasized that the algae should be captured at sea, since removing it after it reaches the shoreline inevitably damages the beaches.
The collected sargassum is also used to manufacture Sargacrete, an environmentally friendly concrete. Approximately 1.5 tons of sargassum are required to produce one cubic meter of the material.
Currently, Sargacrete costs about 10 percent more than conventional concrete but has a lower environmental impact.
“Once sargassum reaches the beach, environmental damage has already begun. When it remains on the shore for several days and begins decomposing, its removal becomes a much more complex, demanding, and necessary task to restore the coastline, reduce environmental impacts, and return this valuable space to both nature and people,” states Grupo Dakatso.
An Urgent Situation
Restaurant owners, tourism operators, and visitors agree that urgent action is needed, although many have become resigned to the current situation.
The conditions are similar throughout Tulum, Cancún, and Playa del Carmen.
There is less turquoise sea than before, making the little that remains seem even more striking.
Source: reforma
